Ending homelessness among Veterans by 2015 is a national priority. Although there are many routes to homelessness, the end result of homelessness frequently involves a failure in planning, problem-solving, or both. Planning and problem-solving are executive functions dependent upon intact brain functioning, and these and other neurocognitive abilities may be impaired in up to 80% of homeless individuals, affecting their organization, judgment, decision-making, and ability to benefit from psychosocial rehabilitation interventions. Thus, cognitive impairment may be an underappreciated yet pervasive barrier to efforts toward ending homelessness. Causes of cognitive impairment in homeless individuals include traumatic brain injury, psychiatric illness, substance abuse, and other medical conditions. Cognitive impairment may interact with these conditions to result in poor housing outcomes, poor treatment adherence, and risk of continued homelessness. Cognitive assessment and rehabilitation in the setting of homeless services is not common, with no known studies to date of cognitive rehabilitation for homeless individuals. We have a golden opportunity to address these research gaps by studying Veterans at the Aspire Center, a 40-bed Residential Rehabilitation Treatment Program (domiciliary) serving homeless returning Veterans with mental health conditions (psychiatric illness, substance abuse, and traumatic brain injuries). In a 15-week randomized controlled trial, Veterans with cognitive or functional impairments will receive an evidence-based, 10-week Compensatory Cognitive Training (CCT) intervention or an education control condition to examine the effects of cognitive rehabilitation in this Veteran population. CCT aims to improve real-world cognitive performance by teaching strategies to improve prospective memory (remembering to do things), attention, learning/memory, and executive functioning. Strategies to reduce stress and improve sleep are also included. CCT has been shown to improve cognition, functional capacity, neurobehavioral symptom severity, and quality of life in individuals with cognitive impairment associated with psychiatric illness and in Veterans with TBI. During the trial, assessments will be administered at baseline, 5 weeks, 10 weeks, and 15 weeks, and monthly follow-up phone calls will assess housing and employment/education status for one year following program discharge. We expect CCT-associated improvements in cognition and functional skills (co-primary outcomes) and generalization to reduced levels of disability, along with improved community reintegration outcomes (better housing stability and participation in work or school). By attending to and treating the cognitive impairments that many of these Veterans will have, we can potentially alter the course of the Veterans' trajectories and prevent future homelessness and its negative health consequences, resulting in both healthcare cost savings and improved quality of life for Veterans.